Forgot your password?
Guest Grossi, May 15, 2016 in Exhaust
Hi Again, I am after some help with a custom exhaust system i want to build for my 77 LTD 351c auto in standard trim. I will be fitting Pacemaker mandrel bent Tri y extractors , which have a final pipe size of 2 1/4 inch. It will be a system. mandrel bent stainless steel pipe. Question
1:do i run 2 1/4 pipe to the y collector then 2.5 inch to the single 2.5 Magnaflow muffler
2: do i run 2.5 from the extractors to the y collector then 2.5 to the muffler
3: do i run 2.5 from extractors to the y collector then 3 inch pipe then reducing it to2.5 to the muffler
Which system would give me the best flow and torque, I am steering towards option 1 as the engine is basically stock but want to allow some room in case i might upgrade the engine to a very mild state in the future.
??? are you runnig a single or dual.
Do the pacemakers merge into 2-1/2 then neck down to 2-1/4 (mine do), or go straight into 2-1/4? If they do neck down, you can cut before that and go 2-1/2 all the way to the Y.
From there, I'd go 3" to the muffler then 2.5 from there. The 3" will act a bit like a resonator and kill some of the harmonics.
In my opinion, 2.5" single muffler and pipes are too small. On a warm 6 that would be perfect, but will start to choke a V8.
Yes its will be a single system as the bumper has only one cut out for the exhaust. the Pacemakers go straight to 2 1/4 as they are 2v Tri y .
i just got mine done on the xe with a single,1 -3/4 primarys then into 2-1/4 then merged into a 3'' single with a stainless hooker aero chamber stright thru and 3'' out v back,very good noise when you open it up,and quiet just putting around,last single i had was a 2-1/2 inch but if i was you i would go a 3''.
If you haven't brought your pacemakers look up Proflow EH4050S, basically the same but stainless steel.
I'd cut the collector for 2.5" exit, 2.5" to Y merge then single 3" with a Hooker aerochamber & 3" tail pipe
I run 2.5" single on stock & mild xflows, My 300hp xflow will be 3" single & my bros ZH & my XE both 302's run 2.5" twin
All ready have the Pacemakers. cost me $430 through a good friend. the LTD will be used cruising so i dont want anything too loud but i am after a deep classy new car sound, no raspy notes.
You'll need a resonator before the magnaflow and another muffler after that if you want that sound, as the magnaflow by itself will only kill a certain frequency. The deep note that you're after will need an offset glasspack before the tailpipe, that will kill any rasp.
Thanks for all your input.
I ended up going 2.1/4 from the heaters then into 2.5 all the way through to the rear. Sound quality is great , nice deep rumble and no resonance around highway cruising. It took all day piecing all the mandrel bends together and getting the correct angles cut, but i am very pleased with the results. Only issue is that with the Pacemaker drivers side extractor they don't weld one of the secondary pipes as it is designed for the early Ford XW which requires cutting the head flange in two so it can be fitted it two pieces. Problem is that on my LTD it can be fitted as one piece but it had a reasonable leak from the slip joint. I fixed it temporarily with some silicone so after a few hundred kilometers it is still holding up . Pacemaker have offered me to supply a new one fully welded or to weld mine up at no charge, so that will be an option it the seal fails . Will try to upload some pictures when i work it out.
I got a similar set to yours, has the split between 1-2 and 3-4 using a slip joint. I needed to install mine separately so I couldn't weld before installing. It still leaks when cold but what helped a bit was cutting some slits horizontally in the outer pipe and clamping it down with a stainless bolt clamp.
Here are some photos (finally) . Mig welding was not as good as a pro but my car is pretty low so you would never see it. No leaks so i am happy
Nothing wrong with imperfect welds on an exhaust. Nobody stops you in the street and tells you how shit your exhaust looks.
merge twin 2.25" into a Y collector with a 3" outlet, if its a mild motor not turning past 5000rpm that'll do, otherwise step it up to a single 3.5" exhaust.
your choice of muffler will denote how loud it is.
putting a hot dog or bullet muffler on the end just before the exit will keep it toned down.
You need to be a member in order to leave a comment
Sign up for a new account in our community. It's easy!
Already have an account? Sign in here.